Beverage cans have made our lives more convenient, as they allow us to carry around cold, carbonated drinks wherever we might be. But they do come with a major downside, in that discarded cans create large amounts of metallic waste that must be recycled or reused in some way. Cans that have just been emptied of their contents are often in very good condition owing to their internal pressure that pushes outwards at all times, and attempting to use the sheet metal for projects can be a painful process since cuts are always a threat. Hackaday.io user Menadue has created a machine that he calls the Can Transformer, and it can take a standard 330ml container and perform a series of precise cuts to turn it into whatever the digital design calls for.
The general concept of the Can Transformer is a CNC lathe that turns a can along a single axis while using two linear axes to make the cuts. The process begins by loading a can in a spring-loaded mechanism, which holds it securely in place. Once ready, the operator can load a custom GCODE script containing the toolpaths for the CNC machine to follow. The X axis slides across the length of the can whereas the can itself spins about the X axis. In concert, these two movements can etch almost any pattern thanks to the attached Proxxon rotary tool equipped with a V-shaped bit that aides in piercing the metal exterior. For now, there are only two heights for the Z axis, although more might be added in the future for more advanced designs.
The X axes are each driven by a single NEMA17 stepper motor and homed with the assistance of a microswitch at the zero point. Both of these motors and the Z axis NEMA11 motor all plug into a Duet 2 Ethernet board. This product is intended for 3D printers and features a powerful ARM Cortex M4F processor, five TMC2660 stepper motor drivers, and a plethora of inputs, but it can be configured for other CNC machine layouts too. Best of all, the Duet 2 has a pleasant web interface where GCODE can be easily uploaded and executed.
Like almost any other CNC machine, the Can Transformer relies on GCODE in order to know what path the toolhead must take. To start, someone must create a design within a DXF file and then run it through a script Menadue wrote that translates the vector image file into GCODE that can be sent to the Duet 2.
So far, Menadue has cut several interesting patterns into a few cans. As seen in his YouTube video about the project, one can features some line-based text that wraps around the center, while another has a series of hexagonal cutouts that are backlit by green LEDs. The last design is simply two pieces of flattened rectangular aluminum sheets that have the words "onions" and "potatoes" dotted across them. To see more about this project, you can read his write-up here on Hackaday.io or watch this demonstration video here on YouTube.